Snap acting electric switch



May 30, 1950 O. o. OAKS sum ACTING ELECTRIC swrrcu Filed Jan. 26, 1949 INVEN TOR. Qriow O. Cak s.

A TTO "NE 75 PatentedMay30, 1950 SNAP ACTING ELECTRIC SWITCH Orion Ottia Oaks, Summit. N. 3., a-ignor, by assignments. to Thermal Lid nldalna,

W New York, N. Y a corporation of Delawm Application January :6. 1940. Serial No. 12,835 Claims. (Cl. 200-140) This invention relates to snap acting electric switches and more particularly to such switches of the mercury tube type actuated by a thermostatic element.

'Heretofore various types of mercury tube type snap acting switches have been proposed for use in various electrical circuits and many of these have been actuated by thermostatic means. Many of these switches are efllcient and of positive operation but others are lacking in simplicity of structure and reliability. The present invention provides a novel snap acting switch of the mercury tube type actuated by a temperature responsive expansible and collaps ible corrugated metallic vessel which is of very simple construction and of reliable and positive action.

It is accordingly an object of the present invention to provide a novel switch of this type which is of simple construction and of positive and reliable action.

Another object of the present invention is to provide such a switch which can be actuated by a suitable thermostatic element.

Another object of the present invention is to provide such a switch which is cheap and easy to manufacture; and readily and easily adjustable.

Other and further objects of the present invention will appear from the following description.

My novel switch is capable of various mechanical embodiments one of which is shown in the accompanying drawings and is described hereinafter to illustrate the invention. This illustrative embodiment of my invention should in no way be construed as defining or limiting the same and reference should be had to the appended claims to determine the scope of this invention.

In the accompanying drawings, in which like reference characters indicate like parts,

Fig. l is a side view, partly in section, of an illustrative embodiment of my invention showing the relative position of the several parts thereof when the thermostatic element is in collapsed position; and

Pig. 2 is an end view of the embodiment of my invention as seen from the right in Fig. 1.

Referring now to the drawing, my novel thermostatically actuated switch is seen to comprise a base element Ill, preferably circular in shape and provided with threads ll so that the same may be suitably secured in the casing (not shown) of an element containing the expansible and collapsible corrugated metallic element l2 which is subject to the temperatures to be controlled.

tension it closed at end l4 andapertured at II. Plug it is mounted for reciprocation within hollow extension II and is internally threaded at I] to receive one end of connecting rod II. A lock nut II is provided to prevent rotation between connecting rod II and plug l4. Connecting rod It extends through aperture i5 and is surrounded by spring 24 which abuts end l4 and lock nut II to force rod and plug l6 downward as seen in Fig. 1. Thermostatic vessel i2 is provided with an actuating post 2| which is of enlarged diameter at 22 to slide in hollow extension I! and to engage plug it.

Rod It may be provided with a suitable aperture 23 through which a tool may be inserted to hold rod II for purposes of adjustment. The upper end of rod I8 is threaded at 24 to receive adjusting housing 25, lock nut 26 being provided to prevent rotation between rod II and housing 25. Housing is axially recessed at its upper end at 21 and diametrically opposed slots 2| open axially into aperture 21. A link 29 is mounted for reciprocation in recess 21 and is provided at its lower end with a pivot 30 extending through both slots 24,

Support 3| is suitably secured to base ID as by screws 32 and extends upwardly to a point above the upper end of housing 25 when housing 25 is in its lowest position. Bell crank 32 is pivoted to support II and 34 and is pivoted at 35 to link 29. Mounting clip 36 is suitably secured to bell crank 33 and is provided with clips 31 surrounding and holding a conventional mercury tube electric switch 38. Switch 38 is provided with electrical leads 39 and 40.

An L-shaped support bracket 4| is suitably secured to base II) as by bolts 42 and carries a pivot pin 43. Rocking link 44 is pivotally mounted on pin 43 and is held thereon by cotter key 45. A pair of snap links 48 are pivotally mounted on rocking link 44 at 41 and are also pivotally mounted on pivot 30. A second pair of snap links 48 are pivotally mounted on support 31 at 49 and are also pivotally mounted on pin 30. One of arms 5 46 is provided with spring support 50 adjacent pivot 41 and the corresponding arm of arms 48 is provided with a spring support 5| adjacent pivot 48. A spring 52 is tensioned between spring supports 50 and 5!.

50 With the embodiment of my invention set up as and post 2| will slide plug it and rod ll up- Base II is provided withahollow upstanding exwardly in extension I! against the action of spring 2| and pivot 3| will be moved upwardly with links it and 40 rotating thereon. Upward movelink}! upwerdlvand'rotatesbell crank -38 about pivotfl rotating switch 38 in a counterclockwise direction. when pivot it passes the center line oi spring 52 spring 82 contracts rotating link 63 to the left and snapping link :9 into its extreme upward position, pivot 39 riding upward in slots 2%, which in turn rotates bell crank 38 in a counterclockwise direction and snaps switch 88 "on" position to position."

When thermostat i2 is cooled it collapses withdrawing post 28 from plug it and spring it moves plug it and rod -58 downwardly. Downward movement oi rod it moves pivot it downwardly and rotates bell crank-8s and switch 38 in a clockwise direction as seen in Fig. 1. This downward movement continues until pivot to the center line of spring 62 at which time spring 82, which has been tensioned by the initial downward movement of pivot 39, retracts and snaps pivot 30 and link 29 to its lowest position in housing 28 rotating bell crank 33 and switch I8 rapidly from "01! position to on position.

said rocking link and said pin, a, second link pivotally engaging said post and said pin, resilient means connecting the pivots c! said links at said post and at said rocking link, a bell crank pivoted on said post and pivotally engaging said slide link and an electric switch operated by said rocker'arm. i

3. In a snap acting switch, a base, a rod slidably mounted in said base, thermostatic means for sliding said rod, resilient means biasing said rod toward said base, means providing an axial slot carried by said rod, 9. pin slidably mounted in said slot, a sliding link carried by said pin, a post secured to said base and spaced from and extending parallel to said rod, a rocking link pivoted to said base and spaced from said rod,

linkage pivoted on said rocking link and pivotally engaging said pin, linkage pivoted on said post and pivotally engaging said pin, tensioned resilient means connecting the pivots of said linkage at said post and at said rocking link and an electric switch actuated by the movement oi said sliding link.

4. In a snap acting switch, a base, a hollow extension for said base, a connecting rod mounted for reciprocation in said hollow extension, resilient means biasing said connecting rod toward said base, an axially bored and laterally slotted It will now be apparent that by the present I invention I have provided-a novel thermostatically actuated snap action mercury tube type electric switch which is of positive and reliable operation; which is cheap and easy to manufacture; which is of simple construction; and which is of easy adjustment.

Changes to or modifications oi the above described illustrative embodiment or my invention may now occur to those skilled in the'art without departing from my inventive concept.

To determine thescope of this invention reference should therefore be had to the appended claims. 7

Whatisclaimedis:

1. In a snap acting switch, a, base, a hollow extension for said base, a connecting rod mounted for reciprocation in said hollow extension, resilient means biasing said connecting rod toward said base, a thermostatic element operating.

through said base and engaging said rod, an axially bored and laterally slotted member adjustably mounted on said rod, a slide link mounted for reciprocation in said axially bored member, a pivot pin carried by said slide link extending through said slots, an upwardly extending support secured to said base, an upwardly extending rocking link pivoted to said base, a pair of snap links pivotally mounted on member adjustably mounted on said rod, a slide link mounted for reciprocation in'said axially bored member, a pivot pin carried by said slide link extending through said slots, an upwardly extending support secured to said base, an upwardly extending rocking link pivoted to said base, a pair of snap links pivotally mounted on said support and pivotally engaging said pin, a second pair of snap links pivotally mounted on said rocking link and pivotally engaging said pin, a spring tensioned between the pivots of 'said pairs of snap links at said support and at said rocking link, and a switch operating a bell crank pivotally-mounted on said support and plvotally engaging said slide link.

5. In a snap acting switch, a. base, a connecting rod mounted for reciprocation in said base, resilient means biasing said rod toward said base, an axially slotted extension for said rod, a pin sliding in said slot, a slide link mounted on said pin, an upwardly extending post mounted .cn said base, an upwardly extending rocking link pivoted to said base, a link pivotally engaging said rocking link and said pin, a. second link pivotallyengaging said post and said pin, re-

said support and pivotally engaging said pin,

a second pair of snap links pivotally mounted on said rocking link and pivotally engaging said pin, a spring tensioned between the pivots 01 said pairs of snap links at said support and at said rocking link, a bell crank pivotally mounted on said support and pivotally engaging said slide link and a tube type mercury switch carried by said bell crank.

2. In a snap acting switch, a base, a connectlm rod mounted for reciprocation in. said base, resilient means biasing said rod toward said base, a thermostat operatively engaging said rod, an axially slotted extension for said rod. 9. pin sliding in said slot, a slide link mounted on said pin, an upwardly extending post mounted on said base. an upwardly extending rocking link pivoted to said base. a link pivotsily engaging silient means connecting the pivots of said links at said post and at said rocking link, and a switch operating a bell crank pivoted on said post and pivotally engaging said slide link.

6. In a snap acting switch, a base, a rod slidably mounted in said base, resilient means biasing said rod toward said base, means providing an axial slot carried by said rod, af'pln slidably mounted in said slot, a switch actuating sliding link carried by said pin, a post secured to said base and spaced from and extending parallel to said rod, a rocking link pivoted to said base and spaced from said rod, linkage pivoted on said rocking link and pivotally engaging said pin, linkage pivoted on said post and pivotally engaging said pin, and tensioned resilient means connecting the pivots of said linkage at said post and at said rocking link.

No references cited. 

